/**
 * POST /api/tasks/[id]/complete - Complete a specific task
 */

import { NextRequest, NextResponse } from 'next/server';
import { requireAuth } from '@/app/lib/auth';
import { findTask, hasUserCompletedTask, createUserTask } from '@/app/lib/db/store';
import { addPoints } from '@/app/lib/points';
import { checkAndAwardBadges } from '@/app/lib/badges';
import { TaskType, UserTask, ApiResponse } from '@/app/lib/types';

export async function POST(
  request: NextRequest,
  { params }: { params: Promise<{ id: string }> }
) {
  try {
    // Authenticate user
    const user = requireAuth(request);
    const { id: taskId } = await params;

    // Find the task
    const task = findTask(taskId);
    if (!task) {
      return NextResponse.json<ApiResponse>(
        {
          success: false,
          error: 'Task not found'
        },
        { status: 404 }
      );
    }

    // Check if task is active
    if (!task.isActive) {
      return NextResponse.json<ApiResponse>(
        {
          success: false,
          error: 'Task is not active'
        },
        { status: 400 }
      );
    }

    // Check if user has already completed this task
    // For certain task types, allow multiple completions
    const allowMultiple = [TaskType.AD, TaskType.VIDEO, TaskType.READING].includes(task.type);

    if (!allowMultiple && hasUserCompletedTask(user.id, taskId)) {
      return NextResponse.json<ApiResponse>(
        {
          success: false,
          error: 'You have already completed this task'
        },
        { status: 409 }
      );
    }

    // Handle quiz tasks separately (they need quiz submission)
    if (task.type === TaskType.QUIZ) {
      return NextResponse.json<ApiResponse>(
        {
          success: false,
          error: 'Quiz tasks must be completed via /api/quizzes/[taskId]/submit'
        },
        { status: 400 }
      );
    }

    // Complete the task
    const userTask = createUserTask(user.id, taskId, task.pointsReward);

    // Award points
    addPoints(user.id, task.pointsReward, `task:${taskId}`);

    // Check and award badges
    const newBadges = checkAndAwardBadges(user.id);

    return NextResponse.json<ApiResponse<UserTask>>(
      {
        success: true,
        data: userTask,
        message: `Task completed! You earned ${task.pointsReward} points${
          newBadges.length > 0 ? ` and ${newBadges.length} new badge(s)!` : ''
        }`
      },
      { status: 201 }
    );
  } catch (error) {
    if (error instanceof Error && error.message === 'Unauthorized') {
      return NextResponse.json<ApiResponse>(
        {
          success: false,
          error: 'Unauthorized'
        },
        { status: 401 }
      );
    }

    console.error('Task completion error:', error);
    return NextResponse.json<ApiResponse>(
      {
        success: false,
        error: 'Internal server error'
      },
      { status: 500 }
    );
  }
}